===== multifactor priority plugin =====

==== basic setup ====

<code>
PriorityParameters      = (null)
PriorityDecayHalfLife   = 14-00:00:00
PriorityCalcPeriod      = 00:05:00
PriorityFavorSmall      = No
PriorityFlags           = FAIR_TREE
PriorityMaxAge          = 14-00:00:00
PriorityUsageResetPeriod = NONE
PriorityType            = priority/multifactor
PriorityWeightAge       = 1000
PriorityWeightFairShare = 1000
PriorityWeightJobSize   = 1000
PriorityWeightPartition = 1000
PriorityWeightQOS       = 1000
PriorityWeightTRES      = (null)
</code>
<code>
scontrol show config |grep -i prio
</code>

----

==== FAIR_TREE ====

  * takes into account all siblings on the same level.
  * better balancing within one account, i.e. users of one account still get a high priority even if their usage is larger than their colleague users within the same account


----

==== sshare ====

  * shows the shares and usages of accounts and users
  * only if multifactor/priority plugin is enabled
  * reset the usage for an account:

<code>
sacctmgr modify account vsctest set RawUsage=0
</code>
  * RawShares: This is the set value when creating the account
  * RawUsage: Usage of the account user; suspected to the PriorityDecayHalfLife
  * Effctv Usage: normalized usage + siblings taken into account
  * FairShare: Factor actually used for calculating the new priority


----

==== priority calculation ====

  * priority from plugin:

<code>
PRIORITY_MF =  AGE + FAIRSHARE + JOBSIZE + PARTITION + QOS + TRES
</code>
  * only contributions if weight in slurm.conf > 0

  * total priority:

<code>
PRIORITY = PRIORITY_MF - NICE
</code>



----

==== nice ====

  * lower negative values means higher priority
  * range is +/- 2147483645.
  * only privileged users can specify a negative adjustment.

===== sprio =====

Only for pending jobs:

<code>
sprio -l
</code>
Set priority explicitly (overrides nice and multifactor):

<code>
scontrol update job <job_id> priority=1
</code>
Restore multifactor:

  * hold job
  * release job

===== cgroups plugin =====

  * limit number of cores and/or memory